A green water-soluble polyester slurry synthesis using MW-assisted glycolysis of recycled PET byproducts to evaluate the sizing performance
Year: 2026
Type: article
Abstract: The escalating environmental burden of polyethylene terephthalate (PET) waste necessitates advanced chemical recycling strategies that combine efficient depolymerization with the direct upcycling of recovered monomers into value-added functional materials. Herein, an eco-efficient microwave (MW)-assisted glycolysis strategy catalyzed by lithium hydroxide (1.2 wt%) was developed to achieve rapid, near-complete depolymerization of waste PET under mild conditions (500 W, 10 min), yielding bis(2-hydroxyethyl) terephthalate (BHET) with a yield of 64.4% and a purity of 95.2%. The synergistic effect of volumetric microwave heating and base-catalyzed transesterification accelerates ester bond cleavage and uniform chain scission while suppressing further degradations. Following solvent extraction and recrystallization, the crude glycolysis products were used directly in a subsequent polycondensation with sodium dimethyl 5-sulfoisophthalate to synthesize a water-soluble polyester (WSP) slurry, thereby reducing energy-intensive purification. Applied as a sizing agent (6 wt% add-on) on staple polyester yarns, WSP significantly enhanced performance by reducing hairiness by 95% and improving abrasion resistance by 61%, while also increasing breaking strength and elongation. Although conventional polyvinyl alcohol (PVA) sizing offered slightly better wear resistance, WSP provided comparable mechanical reinforcement with drastically improved desizing efficiency (3.4%) owing to its intrinsic water dispersibility. This integrated recycling upcycling strategy establishes a closed-loop pathway for transforming PET waste into high-performance textile auxiliaries, accelerating polymer reutilization design, and providing a scalable route toward sustainable textile processing. • The depolymerization time is reduced to 600 s using a 1.2% LiOH catalyst, a 4:1 EG/PET ratio, and 500 W power. • BHET purity of 95.2% is achieved by this technique in glycolysis byproducts. • Glycolysis byproducts enhance the waterborne slurries' performance to reduce yarn hairiness. • The process yields superior desizing properties with excellent mechanical strengths.
Source: Next Sustainability
Language: English
Subfield: Polymers and Plastics
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,280
OpenAlex ID: W7140216398